List Markers

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior. The description adds the valid scopes and a concrete error behavior ('timeline-clip node_id returns a clean error instead of a raw TypeError'), which is useful beyond the annotations; remaining gaps are minor because an output schema exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with purpose and followed by a specific edge-case note. No filler; both sentences earn their place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the simple one-parameter surface, output schema, and rich annotations, the description supplies enough to invoke the tool and understand the main scope/error case. It is less complete on sibling differentiation among marker-list tools, but that is the main remaining gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the one optional node_id parameter is already documented. The description's caveat about a timeline-clip node_id is relevant but also creates some ambiguity against the schema's 'Optional clip node ID to list clip markers' wording, so it does not clearly improve parameter meaning.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('List') and resource ('markers'), and scopes it to the active sequence or a source project item with a marker collection. It is clear enough to act on, but it does not name or distinguish sibling tools such as get_clip_markers or get_sequence_markers_by_type.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives implied usage: use for markers on the active sequence, or on a source project item that exposes a marker collection. It does not explicitly say when to choose it over get_clip_markers/get_sequence_markers_by_type or state exclusions, leaving alternative routing to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.